Question: $ 25^{-\frac{1}{2}}$
$= \left(\dfrac{1}{25}\right)^{\frac{1}{2}}$ Figure out what goes in the blank: $\Big(? \Big)^{2}=\dfrac{1}{25}$ Figure out what goes in the blank: $\Big({\dfrac{1}{5}}\Big)^{2}=\dfrac{1}{25}$ So $25^{-\frac{1}{2}}=\left(\dfrac{1}{25}\right)^{\frac{1}{2}}=\dfrac{1}{5}$